1. Field of the Invention
This invention relates to tannin-containing wood substrates. In one aspect, this invention relates to a latex paint applied to the surface of said substrate. In another aspect, this invention relates to a method of inhibiting tannin migration through the latex paint. In yet another aspect, this invention relates to the use of a poly(N-acyl)alkylenimine as a tannin migration inhibitor.
2. Description of the Prior Art
Harren et al., U.S. Pat. No. 3,494,878, teach incorporating an ion exchange resin into an aqueous coating composition comprised of a dispersed emulsion polymer of vinyl addition type and applying the combination to cedar and redwood type substrates. The ion exchange resin is highly cross-linked.
Nordyke et al., U.S. Pat. No. 3,852,087, teach a method of inhibiting the migration of water-soluble tannins through a paint film applied to a tannin-containing wood by incorporating doping agents into certain composite pigments. Enumerated doping agents included the amphoteric compounds of alumina, titania, zirconium, silica or zinc.
Lalk et al., U.S. Pat. No. 3,900,619, teach inhibiting tannin migration through a latex paint applied to the surface of a tannin-containing wood substrate by applying to the substrate a water-soluble S-arylcycloaliphatic sulfonium compound. These sulfonium compounds can be applied to the wood substrate either prior to or concurrently with the application of the latex paint.
Meyer, "Process of Inhibiting Tannin Migration In Tannin-Containing Wood Substrates", Ser. No. 674,789 and filed Apr. 8, 1976, now U.S. Pat. No. 4,075,394 (Feb. 21, 1978), teaches inhibiting tannin migration in tannin-containing wood substrates by applying to the substrate an aqueous solution of a polyalkylenimine, such as polyethylenimine.